Protein arginine methyltransferases interact with intraflagellar transport particles and change location during flagellar growth and resorption

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Molecular Biology of the Cell 28 (2017): 1208-1222, doi:10.1091/mbc.E16-11-0774.Changes in protein by posttranslational modifications comprise an important mechanism for the control of many cellular processes. Several flagellar proteins are methylated on arginine residues during flagellar resorption; however, the function is not understood. To learn more about the role of protein methylation during flagellar dynamics, we focused on protein arginine methyltransferases (PRMTs) 1, 3, 5, and 10. These PRMTs localize to the tip of flagella and in a punctate pattern along the length, very similar, but not identical, to that of intraflagellar transport (IFT) components. In addition, we found that PRMT 1 and 3 are also highly enriched at the base of the flagella, and the basal localization of these PRMTs changes during flagellar regeneration and resorption. Proteins with methyl arginine residues are also enriched at the tip and base of flagella, and their localization also changes during flagellar assembly and disassembly. PRMTs are lost from the flagella of fla10-1 cells, which carry a temperature-sensitive mutation in the anterograde motor for IFT. The data define the distribution of specific PRMTs and their target proteins in flagella and demonstrate that PRMTs are cargo for translocation within flagella by the process of IFT.This work was supported by National Science Foundation Award MCB 0950402 (R.D.S.), the Ira Allen Eastman (Class of 1829) Professorship at Dartmouth (R.D.S.), which was established in 1910 through a gift to the College by his widow, Jane Eastman, and by a Postdoctoral Fellowship for Research Abroad from the Japan Society for the Promotion of Science (K.M.)

The Wow Factor? A Comparative Study of the Development of Student Music Teachers' Talents in Scotland and Australia

For some time there has been debate about differing perspectives on musical gift and musical intelligence. One view is that musical gift is innate: that it is present in certain individuals from birth and that the task of the teacher is to develop the potential which is there. A second view is that musical gift is a complex concept which includes responses from individuals to different environments and communities (Howe and Sloboda, 1997). This then raises the possibility that musical excellence can be taught. We have already explored this idea with practising musicians (Stollery and McPhee, 2002). Our research has now expanded to include music teachers in formation, and, in this paper, we look at the influences in their musical development which have either 'crystallised' or 'paralysed' the musical talent which they possess. Our research has a comparative dimension, being carried out in Scotland and in Australia. We conclude that there are several key influences in the musical development of the individual, including home and community support, school opportunities and teaching styles and that there may be education and culture-specific elements to these influences

Protein methylation in full length Chlamydomonas flagella

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Cell Motility and the Cytoskeleton 66 (2009): 650-660, doi:10.1002/cm.20387.Post-translational protein modification occurs extensively in eukaryotic flagella. Here we examine protein methylation, a protein modification that has only recently been reported to occur in flagella (Schneider et al. 2008). The cobalamin (vitamin B12) independent form of the enzyme methionine synthase (MetE), which catalyzes the final step in methionine production, is localized to flagella. Here we demonstrate, using immunogold scanning electron microscopy, that MetE is bound to the outer doublets of the flagellum. Methionine can be converted to Sadenosyl methionine, which then serves as the methyl donor for protein methylation reactions. Using antibodies that recognize symmetrically or asymmetrically methylated arginine residues, we identify three highly methylated proteins in intact flagella: two symmetrically methylated proteins of about 30 and 40 kDa, and one asymmetrically methylated protein of about 75 kDa. Several other relatively less methylated proteins could also be detected. Fractionation and immunoblot analysis shows that these proteins are components of the flagellar axoneme. Immunogold thin section electron microscopy indicates that the symmetrically methylated proteins are located in the central region of the axoneme, perhaps as components of the central pair complex and the radial spokes, while the asymmetrically methylated proteins are associated with the outer doublets.This work was supported by NIH DK071720 (rds) and NSF MCB 0418877 (rds)

On being a memory expert witness: Three cases

I describe three legal cases in which I acted as a memory expert witness. The cases contain remarkable accounts of memories. Such memories are by no means unusual in legal cases, are often over retention intervals measured in decades, and contain details the specificity of which is highly unusual. For example, recalling from childhood verbatim conversations, clothes worn by self and others, the weather, actions that at the time could not have been understood, details that could not have been known, precise durations and calendar dates, and much more. I show how our scientific understanding of memory can help courts reach more informed decisions about such fantastical "memories" and how these memories constitute data that as researchers we should seek to understand

Making sense of cilia and flagella

Data reported at an international meeting on the sensory and motile functions of cilia, including the primary cilium found on most cells in the human body, have thrust this organelle to the forefront of studies on the cell biology of human disease

Treatment with selectin blocking antibodies after lengthening contractions of mouse muscle blunts neutrophil accumulation but does not reduce damage

P‐ and E‐selectins are expressed on the surface of endothelial cells and may contribute to neutrophil recruitment following injurious lengthening contractions of skeletal muscle. Blunting neutrophil, but not macrophage, accumulation after lengthening contractions may provide a therapeutic benefit as neutrophils exacerbate damage to muscle fibers, while macrophages promote repair. In this study, we tested the hypothesis that P‐ and E‐selectins contribute to neutrophil, but not macrophage, accumulation in muscles after contraction‐induced injury, and that reducing neutrophil accumulation by blocking the selectins would be sufficient to reduce damage to muscle fibers. To test our hypothesis, we treated mice with antibodies to block P‐ and E‐selectin function and assessed leukocyte accumulation and damage in muscles 2 days after lengthening contractions. Treatment with P/E‐selectin blocking antibodies reduced neutrophil content by about half in muscles subjected to lengthening contractions. In spite of the reduction in neutrophil accumulation, we did not detect a decrease in damage 2 days after lengthening contractions. We conclude that P‐ and/or E‐selectin contribute to the neutrophil accumulation associated with contraction‐induced muscle damage and that only a portion of the neutrophils that typically accumulate following injurious lengthening contractions is sufficient to induce muscle fiber damage and force deficits. Thus, therapeutic interventions based on blocking the selectins or other adhesion proteins will have to reduce neutrophil numbers by more than 50% in order to provide a benefit.In the present study, we tested the hypothesis that P‐ and E‐selectins contribute to neutrophil accumulation in muscles after contraction‐induced injury, and that reducing neutrophil accumulation by blocking the selectins would be sufficient to reduce damage to muscle fibers. Treatment with P/E‐selectin blocking antibodies reduced neutrophil content by about half in muscles subjected to lengthening contractions but did not decrease damage. We conclude that P‐ and/or E‐selectin contribute to the neutrophil accumulation associated with contraction‐induced muscle damage and that therapeutic interventions based on blocking the selectins will have to reduce neutrophil numbers by more than 50% in order to provide a benefit.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117094/1/phy212667.pd

Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip

The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS

Induced pseudoscalar coupling of the proton weak interaction

The induced pseudoscalar coupling $g_p$ is the least well known of the weak coupling constants of the proton's charged--current interaction. Its size is dictated by chiral symmetry arguments, and its measurement represents an important test of quantum chromodynamics at low energies. During the past decade a large body of new data relevant to the coupling $g_p$ has been accumulated. This data includes measurements of radiative and non radiative muon capture on targets ranging from hydrogen and few--nucleon systems to complex nuclei. Herein the authors review the theoretical underpinnings of $g_p$, the experimental studies of $g_p$, and the procedures and uncertainties in extracting the coupling from data. Current puzzles are highlighted and future opportunities are discussed.Comment: 58 pages, Latex, Revtex4, prepared for Reviews of Modern Physic

Maternal Obesity and Developmental Programming of Metabolic Disorders in Offspring: Evidence from Animal Models

The incidence of obesity and overweight has reached epidemic proportions in the developed world as well as in those countries transitioning to first world economies, and this represents a major global health problem. Concern is rising over the rapid increases in childhood obesity and metabolic disease that will translate into later adult obesity. Although an obesogenic nutritional environment and increasingly sedentary lifestyle contribute to our risk of developing obesity, a growing body of evidence links early life nutritional adversity to the development of long-term metabolic disorders. In particular, the increasing prevalence of maternal obesity and excess maternal weight gain has been associated with a heightened risk of obesity development in offspring in addition to an increased risk of pregnancy-related complications. The mechanisms that link maternal obesity to obesity in offspring and the level of gene-environment interactions are not well understood, but the early life environment may represent a critical window for which intervention strategies could be developed to curb the current obesity epidemic. This paper will discuss the various animal models of maternal overnutrition and their importance in our understanding of the mechanisms underlying altered obesity risk in offspring

The Chlamydomonas flagellar membrane glycoprotein FMG-1B is necessary for expression of force at the flagellar surface

Author Posting. © Company of Biologists, 2019. This article is posted here by permission of Company of Biologists for personal use, not for redistribution. The definitive version was published in Journal of Cell Science 132 (2019): jcs.233429, doi:10.1242/jcs.233429.In addition to bend propagation for swimming, Chlamydomonas cells use their flagella to glide along a surface. When polystyrene microspheres are added to cells, they attach to and move along the flagellar surface, thus serving as a proxy for gliding that can be used to assay for the flagellar components required for gliding motility. Gliding and microsphere movement are dependent on intraflagellar transport (IFT). Circumstantial evidence suggests that mechanical coupling of the IFT force-transducing machinery to a substrate is mediated by the flagellar transmembrane glycoprotein FMG-1B. Here, we show that cells carrying an insertion in the 5′-UTR of the FMG-1B gene lack FMG-1B protein, yet assemble normal-length flagella despite the loss of the major protein component of the flagellar membrane. Transmission electron microscopy shows a complete loss of the glycocalyx normally observed on the flagellar surface, suggesting it is composed of the ectodomains of FMG-1B molecules. Microsphere movements and gliding motility are also greatly reduced in the 5′-UTR mutant. Together, these data provide the first rigorous demonstration that FMG-1B is necessary for the normal expression of force at the flagellar surface in Chlamydomonas. This article has an associated First Person interview with authors from the paper.This work was made possible by a Dartmouth FRPDF (faculty research and professional development fund) generously provided by the Dean of the Faculty and by the Ira Allen Eastman (Class of 1829) Professorship, which was established in 1910 by a gift to the College from his widow, Jane Eastman.2020-08-0